[vb.net] VB.NET Inputbox - How to identify when the Cancel Button is pressed?

Although this question is being asked for 5 years ago. I just want to share my answer. Below is how I detect whether someone is clicked cancel and OK button in input box:

Public sName As String

Sub FillName()
    sName = InputBox("Who is your name?")
    ' User is clicked cancel button
    If StrPtr(sName) = False Then
        MsgBox ("Please fill your name!")
        Exit Sub
    End If

   ' User is clicked OK button whether entering any data or without entering any datas
    If sName = "" Then
        ' If sName string is empty 
        MsgBox ("Please fill your name!")
    Else
        ' When sName string is filled
        MsgBox ("Welcome " & sName & " and nice see you!")
    End If
End Sub